BANGUI, Central African Republic  Chadian peacekeeping soldiers opened fire on civilians in Central African Republic's strife-torn capital city over the weekend, killing more than 30 people and sparking fears of reprisal attacks, officials and witnesses said.

Jean-Pierre Sadou, a gendarmerie official with the regional peacekeeping mission could not confirm the death tolls provided by local officials but said the soldiers' actions were a "legitimate defense" after the attack on their convoy.

The soldiers were returning from a mission in the country's interior on Saturday when two of their vehicles were attacked by grenades, said Sadou. In response, the soldiers forced their way past a roadblock erected by French soldiers in Bangui's PK12 neighborhood and started shooting on the crowd, witnesses said.

More than 20 people were killed in the PK12 neighborhood alone, said Odette Dombolo, a commune mayor.

"We continue to collect the bodies," Dombolo said Sunday. "There are more than 100 injured, and I mean seriously. We are overwhelmed."

The same soldiers killed four people in the Gobongo neighborhood, local official Jean Claude Yamodo said, and witnesses said eight more were killed near the airport.

Central African Republic, long one of the world's poorest and most unstable countries, descended into chaos one year ago when an alliance of mostly Muslim rebel groups in the country's north overthrew Francois Bozize, the president of a decade. The rule of the Muslim rebel coalition known as Seleka was marked by atrocities, including tying together victims and throwing them off bridges into rivers to drown or be eaten by crocodiles.

Michel Djotodia, the rebel leader-turned-president, stepped down from power in January amid mounting international pressure. Since then, the country's Muslim minority population has been targeted in often brutal retaliatory violence at the hands of a Christian militia known as the anti-Balaka. Tens of thousands of Muslims have fled for their lives in convoys to neighboring Chad.

All civilians in Bangui are threatened by daily attacks, said the U.N. children's agency. Saturday's violence came just one day after suspected Muslim rebels launched a grenade attack on a funeral, killing at least nine people.

A spokesman for the Christian militia on Sunday called for calm after the shootings by the peacekeepers.

"I invite the entire population and the anti-Balaka in particular to stay calm and to not yield to this provocation," said Brice Emotion Namsio. "We show to the national and international community that this massacre has been perpetrated by Chadian troops on our territory."